For packaging electronic components such as IC and electronic components using IC, an injection tray, a vacuum-formed tray, a magazine, a carrier tape (also called an embossed carrier tape), etc. are used. As such a packaging container, one having an electrically conductive filler dispersed in its surface is used to prevent electronic components such as IC from being destroyed by static electricity, and as the electrically conductive filler, carbon black is widely used, capable of providing a uniform and stable surface resistivity at a low cost.
An electrically conductive sheet comprising a thermoplastic resin having carbon black dispersed therein has such a problem that its mechanical strength and moldability tend to decrease. Patent Documents 1, 2 and the like have been proposed as a method to overcome such a problem. Further, as a sheet for a carrier tape having high mechanical strength and excellent in carbon releasability, Patent Documents 3 and 4 have been proposed. Further, Patent Document 5 has been proposed as a method of imparting easy moldability in various molding methods such as pressure forming, vacuum forming and press molding, and Patent Document 6 has been proposed as a method of improving slitting properties. However, as electronic components become complicated, precise and miniaturized, a packing material has a narrow sheet width and is miniaturized, and electronic components are packaged and mounted at an increasingly high rate. Therefore, a sheet having mechanical strength capable of coping therewith and having high moldability with which molding in a wide temperature range at a low temperature side in various molding methods is possible, has been desired. Further, a conventional carrier tape tends to have burrs and sink marks at the slit portion and the slit edge portion at perforations or center holes of pocket, and such a problem is apparent that they may adversely affect protection of electronic components as miniaturization of the components is in progress.    Patent Document 1: JP-A-57-205145    Patent Document 2: JP-A-62-18261    Patent Document 3: JP-A-2003-512207    Patent Document 4: JP-A-2002-67258    Patent Document 5: JP-A-2005-297504    Patent Document 6: JP-A-2004-185928